Images Credit rStud
Structural Insulated Panels, or SIPs, are a great way to build; you get a strong wall with no thermal bridging and high R-values. Normal stud walls, with insulation packed between wood studs that support both the interior drywall and the exterior sheathing may have an average R-value that complies with code, but heat will be conducted more easily through the stud. In a tightly sealed house with a high humidity, that can lead to condensation and mould.
But not everyone can or wants to build with SIPs, so Earthcore, a Colorado SIP manufacturer, has essentially sliced up a SIP into studs; Like a SIP it is two layers of OSB sandwiched around a urethane core, but you work with it like a conventional stud.
The 2x6 stud has an R-value of 21; conventional wood has an R value of 1.41 per inch, so a conventional 2x6 has an R value of 7.75. One can see instantly that this will go a long way toward reducing thermal bridging.
Preston at Jetson Green was much quicker off the mark than me in getting this up (how does he do it?), and got a lot of great commentary from both people like Chad Ludeman, developer of the 100K house (he thinks the studs are a bit expensive), Brute Force Collaborative, and with good, honest responses from the manufacturer.
There are other ways to get rid of the thermal bridging, including the use of insulated exterior sheathing. I also think that if a slice of a SIP is a good thing, the full wall of SIP is just going to be better, stronger and faster. But it is an interesting idea. More at rSTUD.
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